U.S. patent number 5,501,077 [Application Number 08/250,364] was granted by the patent office on 1996-03-26 for thermoelectric water chiller.
This patent grant is currently assigned to Springwell Dispensers, Inc.. Invention is credited to S. Spence Davis, R. Clark Lucas, Michael J. Nagy, Anthony E. Yeargin, Gerald M. Zinnbauer.
United States Patent |
5,501,077 |
Davis , et al. |
March 26, 1996 |
Thermoelectric water chiller
Abstract
A thermoelectric water-chiller system for cooling bottled water,
and including a mixing valve which enables dispensing of chilled
water, room-temperature water, or a mixture of chilled and
room-temperature water. Components needing periodic cleaning are
readily removable from the system. A fan-cooled thermoelectric-chip
assembly is used to form an ice block which chills the water, and a
variable-speed fan is controlled by a temperature sensor to slow
the fan speed when chilling to a desired temperature is achieved,
and to maintain the ice block at an optimum size.
Inventors: |
Davis; S. Spence (Atlanta,
GA), Lucas; R. Clark (Santa Barbara, CA), Nagy; Michael
J. (Williamsburg, MI), Yeargin; Anthony E. (Charlotte,
NC), Zinnbauer; Gerald M. (Cornelius, NC) |
Assignee: |
Springwell Dispensers, Inc.
(Atlanta, GA)
|
Family
ID: |
22947423 |
Appl.
No.: |
08/250,364 |
Filed: |
May 27, 1994 |
Current U.S.
Class: |
62/3.64; 62/390;
62/397 |
Current CPC
Class: |
B67D
3/00 (20130101); B67D 3/0009 (20130101); F25B
21/02 (20130101); F25B 2321/0251 (20130101) |
Current International
Class: |
B67D
3/00 (20060101); F25B 21/02 (20060101); F25B
021/02 () |
Field of
Search: |
;62/3.64,390,397 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
WO93/08432 |
|
Apr 1993 |
|
WO |
|
WO93/08433 |
|
Apr 1993 |
|
WO |
|
Primary Examiner: Bennett; Henry A.
Assistant Examiner: Ohri; Siddharth
Attorney, Agent or Firm: Cushman Darby & Cushman
Claims
What is claimed is:
1. A drinking-water chiller system, comprising:
a housing;
a tank supported on and extending within the housing;
a thermal insulating member suspended within the tank between upper
and lower ends of the tank to define an upper zone for
room-temperature water and a lower zone for chilled water;
an adjustable proportioning valve mounted on the housing and
coupled to the upper and lower zones for dispensing variable
proportions of room-temperature and chilled water; and
a cooling assembly in the housing, and having a cold-sink plate in
contact with the tank, and a heat sink with a heat-dissipating
means.
2. The system defined in claim 1 in which the proportioning valve
has an inner end which extends into the lower zone of the tank, and
further comprising a locking means engaged with the valve for
releasably securing the valve in position.
3. The system defined in claim 2 in which the locking means is a
member secured to and extending from the thermal insulating member
into releasable engagement with the valve inner end.
4. The system defined in claim 3 in which the locking-means member
is channel shaped to define in combination with a sidewall of the
tank a conduit for passage of room-temperature water from the upper
zone to the proportioning valve.
5. The system defined in claim 4 in which the valve comprises an
outer sleeve engaged with the locking-means member and having a
pair of ports for receiving room-temperature and chilled water, a
rotatable intermediate sleeve fitted within the outer sleeve and
movable to cover and uncover the ports; an inner sleeve fitted
within the intermediate sleeve for conveying water through the
housing; and a spigot secured to an outer end of the inner
sleeve.
6. The system defined in claim 5 in which the cooling assembly
includes a thermoelectric chip positioned between and in contact
with the plate and heat sink, in which the heat sink comprises a
block with a plurality of heat-dissipating fins, and further
comprising a fan in the housing for passing outside air over the
fins.
7. The system defined in claim 6, and further comprising a
plurality of latch assemblies at an upper end of the housing for
releasably securing the tank and thermal-barrier member to the
housing.
8. The system defined in claim 1 in which the cooling assembly
includes a thermoelectric chip positioned between and in contact
with plate and heat sink, and further comprising a temperature
sensing means for measuring temperature at a point in the system
for controlling current flow to the thermoelectric chip.
9. The system defined in claim 8 in which the temperature sensing
means is arranged to measure temperature of the heat sink.
10. The system defined in claim 8 in which the temperature sensing
means is arranged to measure air temperature.
11. The system defined in claim 1 in which the heat sink comprises
a block with a plurality of heat dissipating fins, and further
comprising a variable-speed fan in the housing for passing outside
air over the fins, and a temperature sensor for measuring
temperature at a point in the system, the sensor being connected to
the fan to control fan speed.
12. The system defined in claim 11 in which the cooling assembly
includes a thermoelectric chip positioned between and in contact
with the plate and block, and in which the temperature sensor is
mounted on the heat-sink block.
13. The system defined in claim 11 in which the cooling assembly
includes a thermoelectric chip positioned between and in contact
with the plate and block, and in which the temperature sensor is
arranged to measure air temperature.
14. The system defined in claim 1 in which the tank is arranged to
be removable from the housing, the tank having a bottom wall with a
central opening, and a plate secured to the bottom wall to close
the central opening, and to act as a secondary cold sink.
15. The system defined in claim 14 in which the secondary cold-sink
plate is in face-to-face contact with the cold-sink plate.
16. The system defined in claim 14 in which the secondary cold-sink
plate is a metal plate, and the temperature sensor is a
thermistor.
17. The system defined in claim 11 in which the cooling assembly
includes a thermoelectric chip positioned between and in contact
with the plate and block, and in which the temperature sensor is
mounted on the cold-sink plate.
Description
BACKGROUND OF THE INVENTION
This invention is directed to an improved system for chilling
drinking water, the system being particularly suitable for use with
bottled drinking water. Water cooling is preferably provided by a
thermoelectric heat-transfer module which is quiet and trouble-free
as compared to compressor-type coolers. Heat drawn from the water
by the thermoelectric module is dissipated by fins which are cooled
by fan-driven room air.
The system includes a water reservoir having an upper chamber which
holds substantially room-temperature water, and a lower chamber for
chilled water, and which rests on a cold sink of the thermoelectric
module. Room-temperature water is gradually fed to the lower
chamber as water from that chamber is dispensed. A user-adjustable
mixing valve which will maintain a preset position enables
dispensed water to be drawn from both the room-temperature and
chilled water chambers in a proportion which provides a desired
water temperature.
SUMMARY OF THE INVENTION
The water chiller of this invention has a thermally insulated outer
housing which supports a removable main tank with a lower chamber
for holding chilled water, and a thermal-barrier assembly fitted in
the tank to define an upper chamber for holding room-temperature
water. A thermoelectric cooling system has a cold sink in direct
contact with a heat-conducting metal plate forming the bottom of
the main tank and acting as a secondary cold sink, and a finned hot
sink from which heat is extracted by fan-driven room air.
Preferably, the operating rate of this cooling system is controlled
by varying the fan speed which in turn regulates the hot-sink
temperature and the size of an ice block which forms in the lower
chamber.
The tank and thermal-barrier assembly are secured to the housing by
latches or clips which can be released to enable removal, without
use of tools, of the tank and barrier assembly for convenient
periodic cleaning in a dishwasher. An adjustable proportioning
valve is coupled to both the chilled and room-temperature chambers
to permit mixing of room-temperature and chilled water so the
dispensed water is of a desired temperature. The valve is readily
removable from the tank for cleaning.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional elevation of a thermoelectric water-chiller
system according to the invention;
FIG. 2 is a bottom view of the system;
FIG. 3 is a sectional elevation on line 3--3 of FIG. 2;
FIG. 4 is a sectional elevation on line 4--4 of FIG. 2;
FIG. 5 is a sectional elevation on line 5--5 of FIG. 2;
FIG. 6 is a top view of a main tank of the system;
FIG. 7 is a plan view of a main tank bottom plate;
FIG. 8 is a pictorial view of a bottom cover and channel portion of
a thermal-barrier assembly of the system;
FIG. 9 is a side sectional elevation of a latch assembly in a
closed position;
FIG. 10 is a view similar to FIG. 9, but with the latch assembly in
an open position;
FIG. 11 is a pictorial view of a portion of an upper rim of the
thermal-barrier assembly showing a latch-assembly seat;
FIG. 12 is a pictorial view of a link for the latch assembly;
FIG. 13 is a rear elevation of a clip for the latch assembly;
FIG. 14 is a sectional elevation on line 14--14 of FIG. 13;
FIG. 15 is a pictorial view of the clip;
FIG. 16 is an enlarged sectional elevation of a proportioning valve
assembly;
FIG. 17 is a pictorial view of an outer sleeve of the valve
assembly;
FIG. 18 is a pictorial view of an inner sleeve of the valve
assembly;
FIG. 19 is a pictorial view of a rotatable intermediate sleeve of
the valve assembly;
FIG. 20 is a sectional view on line 20--20 of FIG. 16;
FIG. 21 is a view similar to FIG. 20 showing the rotatable sleeve
of the valve assembly in a different position; and
FIG. 22 is a schematic diagram of an alternative circuit for
thermistor control of electrical energy delivered to a
thermoelectric chip.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A water-chiller system 10 is shown in FIGS. 1-5, the system having
a double-wall and generally cylindrical outer housing 11 with an
upper shell 12, a lower shell 13, and a circular base panel 14. The
upper and lower shells define an enclosed annular space 15 which is
preferably filled with a thermal insulating material such as
closed-cell polyurethane or polystyrene foam plastic. The shells
are joined together at an outer annular joint 18, and by two
threaded fasteners 19 at 180.degree. spacing around the lower end
of the upper shell. The system is supported on four feet 21 (FIG.
5) which, along with base panel 14, are secured to the housing by
threaded fasteners 22.
A generally cylindrical main tank 24 for holding chilled water has
an inwardly tapered bottom portion 25 defining a central circular
opening 26. The upper end of the tank has a radially outwardly
extending annular lip 27 which seats on a resilient seal ring
against an upper end 28 of upper shell 12 when the tank is fitted
within the housing as shown in FIG. 1. The bottom of the tank is
closed by a thin stainless-steel circular plate 30 (FIG. 7) which
extends across opening 26, and is secured in place by four screws
31 (FIG. 5). A thick resilient ring-shaped gasket 32 between the
tank and plate provides a fluid-tight seal.
To minimize heat transfer between room-temperature and chilled
water in the system, a thermal-barrier assembly 35 is fitted within
the upper end of main tank 24 to form an upper chamber for the
room-temperature water. The assembly has a generally cylindrical
sidewall 36, and a bottom wall 37. An outwardly and downwardly
extending annular lip 38 extends from the upper end of sidewall 36
to overhang and rest against the upper end of the main tank.
An annular recess 39 is formed in the undersurface of bottom wall
37, and a circular bottom cover 40 (FIGS. 1 and 8) is secured
(e.g., by sonic welding) at its upper edge in the recess. A space
41 defined between the bottom wall and bottom cover is filled with
a circular disk 42 of a thermally insulating material such as
polystyrene foam plastic.
As shown in FIG. 1, a conventional five-gallon water bottle 44 is
inverted and supported on annular lip 38 of the thermal-barrier
assembly. Bottled water at room temperature thus fills the upper
chamber of system 10 within sidewall 36 above bottom wall 37, and
is admitted to a lower chamber of main tank 24 through sidewall
openings 45. In an alternative form, sidewall 36 can be replaced
with a series of struts (not shown) between which water can flow
around the thermal barrier (which can be enlarged in diameter) into
the lower chamber. In either case, the desired effect is to
maintain stratification of the room-temperature water and chilled
water, and thereby to achieve rapid chilling of water in the lower
part of the main tank. Use of a plurality of relatively small flow
passages from the upper chamber to the lower chamber provides
low-velocity admission of warm water to minimize swirling and
mixing of water in the lower chamber.
The main tank and thermal-barrier assembly are secured within
housing 11 by three or four circumferentially spaced
fastening-means latch assemblies 46 shown in detail in FIGS. 9-15.
The assemblies are fitted in recesses 47 formed in lip 38 which is
the upper and outer rim of the thermal-barrier assembly as shown in
FIG. 11. A pair of spaced-apart and upwardly open saddles 48 are
formed in the opposed sides of each recess 47, and blind
cylindrical sockets 49 in alignment with the saddles extend into
lip 38.
A link 50 used in each latch assembly is best seen in FIG. 12, and
is a molded plastic part with a pair of spaced-apart lower ears 51
through which are formed coaxial bores 52. A bore 53 extends
longitudinally through an upper portion of the link, and the axes
of bores 52 and 53 are parallel. The link is hinged to and
supported in recess 47 by a pair of spaced-apart pins 54 (FIGS. 9
and 10) fitted through bores 52 to extend across and rotatably rest
on saddles 48, with the outer ends of the pins making a press fit
into blind sockets 49.
A clip 57 used in each lock assembly is best seen in FIGS. 13-15,
and is an integrally molded plastic part having a sidewall 58, and
an upper locking tongue 59 extending inwardly from the upper end of
the sidewall. A lower locking tongue 60 extends inwardly from the
lower end of the sidewall, and stiffening ribs 61 are formed on the
inner surface of the sidewall. A pair of spaced-apart ears 62 also
extend from the inner surface of the sidewall, and the ears have
coaxial bores 63 therethrough. The upper portion of link 50 is
fitted between ears 62, and the link and clip are pivotally secured
together by a pin 64 (FIGS. 9-10).
The latch assembly is shown in an open or disengaged position in
FIG. 10, and the main tank and thermal-barrier assembly can be
upwardly withdrawn from the system outer housing when the
lock-assembly clips are so positioned. When these components are
reinstalled in the outer housing, each clip 57 is hinged upwardly
and inwardly to engage lower locking tongue 60 against a shoulder
66 formed at the upper part of a recess 67 in the outer surface of
upper shell 12 of the outer housing (FIGS. 9-10). The clip is then
further pressed inwardly to the closed position shown in FIG. 9
with upper locking tongue 59 extending over and pressed against
shoulders 68 (FIG. 11) formed at opposite ends of each recess 47 of
the upper rim of the thermal-barrier assembly. Resilient annular
seals 69 and 70 are positioned between the thermal-barrier
assembly, main tank, and outer housing (FIGS. 1 and 9-10) to
prevent entry of moisture into the spaces between the main tank and
outer housing.
A particular feature of this invention is a proportioning valve
assembly 73 (FIGS. 4 and 16-19) which enables dispensing of chilled
water only, room temperature water only, or a selectable mixture of
chilled and room-temperature water. The valve assembly extends
through and is supported by a horizontally positioned cylindrical
outer tube 74 which extends through openings 75 and 76 in upper and
lower shells of the housing, and is clamped in place by an inner
snap-in retaining ring 77 fitted against an O-ring seal 78.
The valve assembly includes a cylindrical outer sleeve 80 (FIGS.
16-17) with an enlarged and outwardly tapered head 81 at its outer
end. An annular recess 82 is formed in the tapered head, and
extends circumferentially about 100.degree.. A bore 83 extends
axially through the sleeve, and the diameter of the bore is
slightly decreased as it passes through an inner end wall 84. A
pair of oppositely oriented keyway slots 85 spaced at 180.degree.
are formed in the end wall. A pair of oppositely oriented upper and
lower rectangular ports 86 and 87 are spaced at 180.degree., and
formed through the sidewall of the outer sleeve adjacent the end
wall. Annular grooves 88 and 89 are provided on the sleeve outer
surface to receive O-ring seals.
A rotatable intermediate sleeve 91 (FIGS. 16 and 19) makes a slip
fit within bore 83 of the outer sleeve, and has at its outer end a
radially extending flange 92 which seats in a mating recess in head
81 of the outer sleeve. A rotation arm 93 extends radially from
flange 92, and the arm seats in annular recess 82 such that arm
movement (and hence rotation of the intermediate sleeve) is limited
by the extent of the recess. The intermediate sleeve has an inner
portion 94, and a 180.degree. slot 95 is formed through the
sidewall of this portion adjacent the inner end of the sleeve.
A fixed-position inner sleeve 98 (FIGS. 16 and 18) makes, a slip
fit within the intermediate sleeve, and has at its inner end an
enlarged head 99 which seats against the inner end of outer sleeve
80. A bore 99A extends through the inner sleeve to terminate at
head 99. A pair of opposed 180.degree.-spaced lugs or keys 100
extend axially from the inner side of the head, and are positioned
to mate with keyway slots 101 (FIG. 16) in the end wall of the
outer sleeve. A pair of 180.degree.-spaced opposed ports 103 extend
through the sidewall of the inner sleeve into bore 99A adjacent
head 99.
An outer end 104 of sleeve 98 is threaded to receive a conventional
dispensing valve or spigot 105 (FIGS. 4 and 16) having at its inner
end a flange 106 which is positioned immediately adjacent or
against the outer end of tapered head 81 of outer sleeve 80. The
outer sleeve and intermediate sleeve are thus clamped between
flange 106 and enlarged head 99 at the inner end of inner sleeve
98, enabling valve assembly 73 to be inserted into or withdrawn
from the housing as a unit. Flange 92 of intermediate sleeve 91 is
dimensioned to make a slip fit against flange 106 of the spigot to
permit rotation of the intermediate sleeve. The inner portion of
the valve assembly extends through a circular opening 108 formed in
the lower sidewall of tank 24 to position lower port 87 of outer
sleeve 80 in communication with chilled water in the tank.
A vertical channel 110 (FIGS. 8 and 16) is integrally formed with
and extends downwardly from one side of bottom cover 40 of
thermal-barrier assembly 35. Channel 110 performs the dual
functions of conveying room-temperature water from above the
thermal-barrier assembly to valve assembly 73, and clamping the
inner end of the valve assembly within the lower end of tank
24.
Channel 110 has a base 111, and a pair of radially outwardly
extending and spaced-apart sidewalls 112 which define at their
outer ends oppositely extending circumferential ribs 113. A pair of
inwardly extending shoulders 114 are formed at a lower portion of
sidewalls 112, and lower surfaces 115 of the shoulders are
cylindrically curved to fit against the inner portion of outer
sleeve 80. An O-ring seal 117 is fitted in groove 89 around the
outer sleeve to seal the valve assembly to the tank. Sidewalls 112
also define inwardly extending ribs 118 dimensioned to make a snug
slip fit within keyway slots 85 of the outer sleeve.
As best seen in FIG. 6, a pair of downwardly and inwardly extending
spaced-apart tapered guide ribs 120 are integrally formed in the
inner surface of tank 24. Ribs 113 of channel 110 of the
thermal-barrier assembly make a snug slip fit within mating guide
ribs 120 to clamp the channel sidewalls in sealed engagement
against the inner sidewall of the tank. Channel 110 and the tank
sidewall between guide ribs 120 thus form a conduit 121 permitting
room-temperature water to flow by gravity through a port 122
(formed through bottom wall 37 as shown in FIGS. 4 and 16) to upper
port 86 of the valve-assembly outer sleeve (FIGS. 20-21).
A thermoelectric chilling assembly 124 (FIGS. 3-5) is positioned in
a space 125 at the bottom of system 10 between base panel 14 and
the lower end of outer housing 11. Assembly 124 has at its upper
end a thick circular aluminum cold-sink plate or disk 126 around
the perimeter of which is insert-molded a plastic clamping ring 127
which engages a radially outwardly extending flange 128 on the
lower end of the disk. A hot-sink aluminum block 130 is positioned
below and slightly spaced from the undersurface of disk 126, and a
thermoelectric chip 131 (commercially available types such as
supplied by Materials Electronic Products Corporation in Trenton,
N.J. are suitable) is sandwiched tightly between the top of block
130 and disk 126. The lower part of block 130 defines a plurality
of downwardly extending heat-dissipating fins 132.
The components of chilling assembly 124 are secured together by
four 90.degree.-spaced bolts 133 with shanks passing through
clearance holes 134 in block 130 to thread into clamping ring 127
as shown in FIG. 3. Assembly 124 is in turn secured to the
undersurface of upper shell 12 of the outer housing by four
90.degree.-spaced bolts 135 (the heads of which are accessible
through openings 136 in the hot-sink block) having shanks which
pass through clearance holes 137 in the clamping ring to thread
into bosses 138 at the bottom of upper shell 12 as shown in FIG.
5.
A thermally controlled variable-speed fan 140 (FIG. 4) is secured
to base panel 14, and slides upwardly into a cavity formed at the
lower end of outer-housing lower shell 13 when the base panel is
installed. An apertured air-outlet grill 141 is supported on the
lower shell adjacent the discharge side of the fan. A temperature
sensor such as a thermistor 142 (other types of temperature
transducers such as a self-generating thermocouple are of course
also suitable when used with compatible circuitry) is secured to
the hot-sink block, and is coupled to speed-control circuitry in
fan 140 by a cable 143. Outside room air is drawn by the fan
through a plurality of inlet slots 144 (FIG. 2) formed through base
panel 14 to pass over and draw heat from fins 132.
Fan 140 is of a commercially available type (suitable units are
available from Comair Rotron, Inc., in San Ysidro, Calif., or Sanyo
Denki Co. Ltd., in Japan) which regulates fan speed according to
the temperature sensed by thermistor 142. Fan speed is thus
automatically diminished as the temperature of the hot-sink block
decreases when water in the tank has been chilled or the room-air
temperature becomes colder. Fan speed is correspondingly increased
when a higher rate of heat transfer out of the tank is needed. The
control circuitry of the fan can be adjusted to match a specific
range of fan speeds with a specific range of sensed
temperatures.
Twelve-volt d-c power is provided to thermoelectric chip 131 and
fan 140 by a transformer and rectifier assembly 143 (FIG. 3)
secured to base panel 14 and positioned within a cavity 145 formed
in the bottom of lower shell 13 of the outer housing. The
transformer is connected to a standard a-c power outlet, and
cabling from the assembly 143 to the thermoelectric chip and fan is
omitted from the drawings for clarity.
The thermoelectric chip operates in a conventional way to draw heat
from the cold-sink disk (and hence from water in the tank through
plate 30 (acting as a kind of secondary cold sink) which is tightly
positioned in face-to-face contact with the upper surface of the
cold-sink disk) to be dissipated to outside room air by fins 132
which are cooled by air sucked by the fan through base-panel slots
144 into the plenum surrounding the fins. Though the control of
cooling action is preferably provided by varying the fan speed (and
thus reducing fan noise during "idling" operation when the tank
water has been fully chilled), an acceptable alternative is to vary
the current supplied to the thermoelectric chip in response to
varying heat loads.
FIG. 22 shows a typical arrangement of conventional circuit
elements for controlling the operating level of the thermoelectric
chip. A transformer, full-wave rectifier, and smoothing capacitor
form a power supply 147 for converting a-c line voltage to direct
current. A constant-speed fan motor 148 is connected across the
power supply, and a low-dropout voltage regulator 149 (a Texas
Instruments LT1084C regulator is suitable) in series with a
thermoelectric chip 150 is also connected across the d-c output of
the power supply. Temperature at a point in the system is sensed by
a transducer such as a thermistor 151 which controls regulator 149
to vary the voltage, and hence current flow to chip 150.
Temperature may also be sensed at other points in or external to
the system such as at the chip, at the cold sink, in the body of
chilled water (the latter approach having the disadvantage of
penetration of the tank by the sensor), or in the room air
surrounding the system. Sensing of temperature at the hot-sink
block, however, is presently preferred, because it provides good
control of ice-block buildup and final size responsive to
temperature changes in both the chilled water and the room air. As
mentioned above, the temperature signal from the sensor may also be
used to control a variable current flow to the thermoelectric
chip.
In use, thermoelectric chilling assembly 124 forms an ice block 155
(shown in phantom line in FIG. 4) in the bottom of the tank for
rapid chilling of room-temperature water admitted from the upper
chamber into the lower chamber. Water is dispensed through spigot
105, and temperature of the dispensed water can be adjusted by
rotating intermediate sleeve 91 of the valve assembly. The
intermediate sleeve has sufficient frictional resistance to
rotation to maintain a desired preset position. A mixture of
room-temperature and chilled water is provided by positioning the
sleeve as shown in FIG. 20. If only room-temperature water is
needed, the sleeve is rotated to the position shown in FIG. 21 with
lower port 87 of the outer sleeve blocked, and upper port 86 fully
open. Clockwise rotation of sleeve 91 to a position opposite that
shown in FIG. 21 blocks the upper port, and permits only chilled
water to be dispensed through the lower port.
A significant advantage of the invention is the ease of removing
tank 24 and thermal-barrier assembly 35 for periodic dishwasher
cleaning. Disassembly involves removal of the water bottle, release
of clips 57 and upward withdrawal of the thermal-barrier assembly.
The thus unclamped valve assembly 73 can then be pulled outwardly
within outer tube 74 out of engagement with tank 24 so the tank can
be withdrawn from the outer housing. Reassembly involves only a
reversal of these steps. The general arrangement of the tank,
thermal-barrier assembly, and associated latches make the chiller
system well adapted for mounting of a probe used to open resealable
caps which are now available for bottled-water containers.
To maintain good cooling efficiency, it is important that
stainless-steel plate 30 forming the sealed bottom of the tank be
clamped in intimate face-to-face contact with the upper surface of
cold-sink disk 126. A degree of resiliency is provided in the
system to accommodate tolerance errors of the plastic and metal
parts by thick gasket 32 which is only partially compressed when
clamping screws 31 are fully seated. Further compression of the
gasket permits an "over center" action of clips 57, and the
restoring force exerted by the gasket urges plate 30 against the
cold-sink disk. The desired resiliency of the system can also be
provided by other elastomeric members such as seals 69 and 70, or
by using a resilient spring-loaded mounting for the thermoelectric
chilling assembly.
There has been described a thermoelectric water-chiller system
which provides efficient cooling of bottled water for personal
consumption and use, with quiet, reduced-noise operation after the
water has been fully chilled. The system is designed to enable
ready and simple disassembly for periodic cleaning, and this
feature is believed to be equally useful in compressor-type water
coolers. The system is not restricted to use with bottled water,
and can be adapted for water-treatment systems of the point-of-use
type.
* * * * *